We have several Adeunis ARF8200AA transceivers which send data to our loraserver every ten minutes via several multitech gw. On each gateways is the LoRa Gatewy Bridge installed.
Regardless of how long they have sent data before, we got the error message described in the topic.
For example the excerpts for two devices from the loraserver logfile.
Somebody an idea what the reason for this behavior is?

Thank you very much for your analysis. After your answer, I opened a case by Adeunis.
You were right about your analysis. There is a problem with the firmware.
Here is the answer to my request at Adeunis.

The behavior you describe is a problem with our devices responding to this Mac command.
This behavior will be solved by upgrading the FW of the devices to make them compliant with the LoRaWAN 1.0.2 RevB specifications.